NAME

       tmpfiles.d - Configuration for creation, deletion and cleaning of volatile and temporary
       files

SYNOPSIS

       /etc/tmpfiles.d/*.conf

       /run/tmpfiles.d/*.conf

       /usr/lib/tmpfiles.d/*.conf

DESCRIPTION

       systemd-tmpfiles uses the configuration files from the above directories to describe the
       creation, cleaning and removal of volatile and temporary files and directories which
       usually reside in directories such as /run or /tmp.

CONFIGURATION FORMAT

       Each configuration file shall be named in the style of <program>.conf. Files in /etc/
       override files with the same name in /usr/lib/ and /run/. Files in /run/ override files
       with the same name in /usr/lib/. Packages should install their configuration files in
       /usr/lib/. Files in /etc/ are reserved for the local administrator, who may use this logic
       to override the configuration files installed by vendor packages. All configuration files
       are sorted by their filename in alphabetical order, regardless in which of the directories
       they reside, to guarantee that a specific configuration file takes precedence over another
       file with an alphabetically later name.

       If the administrator wants to disable a configuration file supplied by the vendor the
       recommended way is to place a symlink to /dev/null in /etc/tmpfiles.d/ bearing the same
       file name.

       The configuration format is one line per path containing action, path, mode, ownership,
       age and argument fields:

           Type Path        Mode UID  GID  Age Argument
           d    /run/user   0755 root root 10d -
           L    /tmp/foobar -    -    -    -   /dev/null

   Type
       f
           Create a file if it doesn't exist yet (optionally writing a short string into it, if
           the argument parameter is passed)

       F
           Create or truncate a file (optionally writing a short string into it, if the argument
           parameter is passed)

       w
           Write the argument parameter to a file, if the file exists. Lines of this type accept
           shell-style globs in place of normal path names. The argument parameter will be
           written without a trailing newline. C-style backslash escapes are interpreted.

       d
           Create a directory if it doesn't exist yet

       D
           Create or empty a directory

       p
           Create a named pipe (FIFO) if it doesn't exist yet

       L
           Create a symlink if it doesn't exist yet

       c
           Create a character device node if it doesn't exist yet

       b
           Create a block device node if it doesn't exist yet

       x
           Ignore a path during cleaning. Use this type to exclude paths from clean-up as
           controlled with the Age parameter. Note that lines of this type do not influence the
           effect of r or R lines. Lines of this type accept shell-style globs in place of normal
           path names.

       X
           Ignore a path during cleanup. Use this type to prevent path removal as controlled with
           the Age parameter. Note that if path is a directory, content of a directory is not
           excluded from clean-up, only directory itself. Lines of this type accept shell-style
           globs in place of normal path names.

       r
           Remove a file or directory if it exists. This may not be used to remove non-empty
           directories, use R for that. Lines of this type accept shell-style globs in place of
           normal path names.

       R
           Recursively remove a path and all its subdirectories (if it is a directory). Lines of
           this type accept shell-style globs in place of normal path names.

       z
           Restore SELinux security context label and set ownership and access mode of a file or
           directory if it exists. Lines of this type accept shell-style globs in place of normal
           path names.

       Z
           Recursively restore SELinux security context label and set ownership and access mode
           of a path and all its subdirectories (if it is a directory). Lines of this type accept
           shell-style globs in place of normal path names.

   Mode
       The file access mode to use when creating this file or directory. If omitted or when set
       to - the default is used: 0755 for directories, 0644 for all other file objects. For z, Z
       lines if omitted or when set to - the file access mode will not be modified. This
       parameter is ignored for x, r, R, L lines.

   UID, GID
       The user and group to use for this file or directory. This may either be a numeric
       user/group ID or a user or group name. If omitted or when set to - the default 0 (root) is
       used. For z, Z lines when omitted or when set to - the file ownership will not be
       modified. These parameters are ignored for x, r, R, L lines.

   Age
       The date field, when set, is used to decide what files to delete when cleaning. If a file
       or directory is older than the current time minus the age field it is deleted. The field
       format is a series of integers each followed by one of the following postfixes for the
       respective time units:

       s, min, h, d, w, ms, m, us

       If multiple integers and units are specified the time values are summed up. If an integer
       is given without a unit, s is assumed.

       When the age is set to zero, the files are cleaned unconditionally.

       The age field only applies to lines starting with d, D and x. If omitted or set to - no
       automatic clean-up is done.

       If the age field starts with a tilde character (~) the clean-up is only applied to files
       and directories one level inside the directory specified, but not the files and
       directories immediately inside it.

   Argument
       For L lines determines the destination path of the symlink. For c, b determines the
       major/minor of the device node, with major and minor formatted as integers, separated by
       :, e.g. "1:3". For f, F, w may be used to specify a short string that is written to the
       file, suffixed by a newline. Ignored for all other lines.

EXAMPLE

       Example 1. /etc/tmpfiles.d/screen.conf example

       screen needs two directories created at boot with specific modes and ownership.

           d /var/run/screens  1777 root root 10d
           d /var/run/uscreens 0755 root root 10d12h

SEE ALSO

       systemd(1), systemd-tmpfiles(8), systemd-delta(1)